Much of the material in Unearthed Arcana had previously appeared in Dragon magazine, and was later (in second edition) incorporated directly into Player's Handbook and Dungeon Master's Guide. Some other additions, like Comeliness attribute, were not included in the core, but were used almost everywhere. The new classes and character races presented in Unearthed Arcana were left out of the next version of the Player's Handbook, as they were considered unbalanced by the AD&D 2nd Edition's designers (the book's author, Gary Gygax, has left the team by that time), but were revitalised anyway in the following supplements.